On Thu, Oct 2, 2008 at 13:47, Chris Hamons <chris.hamons@xxxxxxxxx> wrote: > I've been told that in gcc 3.3, reading from std::string was not > thread safe, and that in gcc 4.x it is now thread safe. Is this > correct? Is it thread safe to iterate through a std::vector in gcc 3.3 > or gcc 4.x. I have not been able to find any documentation on what is > and isn't threadsafe when it comes to stl and gcc. > In general, simultaneous reads of any std:: container are thread-safe. However, as soon as you want to use any mutating function on a container, all read and write accesses need to be mutexed. None of them are lock-free. For std::string, it's possible that it was ref-counted at some point, which makes it harder to know which functions are mutating. Not authoritative, but I hope it helps, ~ Scott
